OZY Fest, our annual festival of ideas, music, comedy and food, was canceled by the City of New York this past weekend as temperatures rose to their highest in seven years. The heat wave, demonstrative of broader climate changes, is sweeping large parts of North America. Across the Atlantic, France last month saw an all-time high temperature of 113 degrees. In Italy, 16 cities issued heat-related alerts in June, and several regions of Germany, Poland and Switzerland experienced record high temperatures. Meanwhile, Spain battled its biggest wildfires in 20 years. Yet the news isn’t all grim. From Bangalore to Manhattan, revolutions in renewable energy, reforestation and water usage are offering hope. OZY’s series “The New Frontiers of Climate Change” focuses on people and teams around the world who are coming up with surprising but potentially game-changing ways to fight global warming.

First-year medical student Anna Goshua was interviewing an emergency room physician in March to learn more about the job when she heard about a patient who had come all the way from Puerto Rico to that ER in Massachusetts for health care. Hurricane Maria had wiped out all prospects of the patient seeking care at home.

A surprised Goshua pored over her Stanford University curriculum to learn more about climate migrants. She realized the school offered no coursework about mental or physical illnesses linked to climate change, nor about the ways in which climate change is changing health care access. While the physical health impacts of climate change crises are more obvious, a growing volume of research over the past five years has demonstrated how changing weather patterns are also leading to a ballooning global mental health burden. That’s both in the form of increasing depression and anxiety about the growing crisis, as well as mental health conditions that stem from climate change effects. The American Psychological Association in a March 2017 report said the “tolls on our mental health [from climate change] are far-reaching.” Yet until now, universities have been slow to incorporate the subject into their programs.

Think of movies about climate change, and you likely imagine giant waves sweeping coastal metropolises from New York to Shanghai. But while island nations — such as the Pacific Islands and Haiti — and coastal cities risk devastation caused by global warming, there’s a country that’s even more vulnerable. The good news? It’s fighting back and offering lessons to others.

Chad won’t drown. But a combination of extreme poverty, a large refugee population and decreasing rainfall in the agriculture-dependent society mean that short of being physically wiped out, the central African nation could suffer even more from shifting climatic conditions than oceanic countries. According to a 2016 study by British global risk analysis firm Verisk Maplecroft, landlocked Chad is the country most vulnerable to the adverse effects of climate change.